The military-industrial scientific research system of the academic master.

Ice City, 602 Research Institute.

Wang Zhilin, an engineer who had just graduated from Bingcheng University of Technology, was burying his head in front of a computer, staring anxiously at the calculation data that unhurriedly popped up one by one on the screen.

The 602 Institute is called the "Cradle of China's Helicopter Industry", which sounds nice to say, but because in the past few decades, China has not seriously equipped many decent helicopters, and most of them are imported models, so this cradle …

At least so far, no reason has been revealed.

直5只是一种50年代初期技术水平的早期活塞直升机，直6和直7中道崩殂，直8属于昌河，而直9……

Zhijiu was on the computer screen in front of Wang Zhilin.

The vast majority of the "Dolphin" family currently serving in the Chinese army are SA365N1 imported or assembled with imported materials, which is the French prototype of the Z-9.

The real Z-9 has just been delivered to the troops stationed in Hong Kong for 6 aircraft not long ago, and the civilian model has only found two intended users...

In fact, even the main rotors, tail rotors and transmission systems of this batch of aircraft use a large number of serially assembled parts, that is, original SA365N1 parts purchased directly from the French Aerospace Company and installed on the aircraft.

The engine is directly imported from the Ahaye 1C.

It is somewhat similar to the current state of the J-11.

Under such circumstances, Institute 602 naturally does not have enough funds to purchase advanced supercomputers like Institute 601 or Institute 611.

But the advent of a new era, especially the sudden rise of a young man named Chang last year, has made everyone aware of the value of digital design.

So in the end, 602 Institute still squeezed out some of its scientific research funds and purchased a cost-effective server from Sugon Company.

But the price is quite poor performance.

Wang Zhilin is currently calculating the strength margin of the main reducer tail output transmission bevel gear pair. In theory, it is not a particularly complicated thing, but just outputting the data has already taken half a morning.

This is because the new TORCH Multiphysics software has greatly improved the calculation efficiency. Otherwise, if you use the old structural mechanics calculation software, 80% of the calculations will get stuck in the middle.

"Sigh... That's okay, the pace is slower, suitable for a slow person like me..."

While comforting himself, Wang Zhilin wrote the last number on the screen on the design diagram of the entire machine's transmission system spread out on the table in front of him, and then stretched out:

"It's been half a month, and I finally finished all these things..."

It must be admitted that France Aerospace did not hide any secrets when transferring the technical data of SN365N1.

The entire introduction process of Z-9 went smoothly, as if the French had been caught by China.

Not only does it include a full set of technical information, but it also includes independent export rights in the contract for the first time.

This is an extremely rare situation.

Even for the J-11 in today's timeline, Sukhoi has even given the authority to jointly modify it to the 601 Institute and the 112 Factory, but it has also insisted that China cannot export the Flanker series of fighter jets and their equipment to any third party. Any improvements based on the model.

So logically speaking, the research and development of the Zhi-9 project should be very simple.

However, the transmission system produced by the Bingcheng 122 Factory in China has always failed to meet the performance requirements. As a result, the subsequent naval-type Z-9C was obviously replaced with a turboshaft 8F engine with better performance, but the actual available output power did not increase. Fall instead.

The final result is that an aircraft can only carry one of submarine search sonar and anti-submarine torpedoes. At least two Z-9Cs are needed to complete the submarine search-submarine attack task process...

Very outrageous.

Wang Zhilin was trying to solve this problem at this time.

"The maximum allowable output power of the main rotor is 800kW, the maximum allowable input power on both sides is 900kW, the upper limit of the single-stage oil pump speed is 3800, and the oil pressure under working conditions is 0.17-0.26Mpa..."

He picked up the red and blue pencils at hand and circled the numbers recorded on the design drawings in the past few days with red or blue pens.

"No problem...how could the available power be reduced..."

The maximum continuous output power of the turboshaft 9F engine equipped on the Zhi-8C has been increased from the original 437kW to 496kW. However, no matter how you calculate it, it is still within the allowable limits of the entire transmission system and has sufficient margin, even if the processing accuracy of China's side cannot reach it. The original D-class of French Aerospace should not have the situation where the input power increases and the output power decreases instead.

Wang Zhilin, who felt his brain was a little bloated, simply threw the pencil aside and opened the tutorial that came with the TORCH Multiphysics software on his computer.

This is one of his favorite leisure activities in recent days.

Generally speaking, no one will look specifically at the "Help" interface of the software. However, it is said that this tutorial was personally completed by Chang Haonan, a legendary figure in the industry who has been named a demigod and the developer of the software.

Wang Zhilin didn't take it seriously at first, but he just opened it one time to pass the time.

Unexpectedly, after seeing this, I became addicted.

Even if the content writer is not Chang Haonan himself, he is definitely a person with profound attainments in the field of numerical computing.

From then on, he began to read this part whenever he had time.

"and many more……"

Soon, Wang Zhilin saw what he was interested in:

"Tail output bevel gear pair..."

He was suddenly inspired by the contents of one of the calculation examples.

"Yes, it is not only the main rotor that affects the helicopter's power output, but also the tail..."

He quickly reopened the project file for the transmission system modeling and imported it into TORCH Multiphysics.

However, this time the focus of his research became the rear part of the helicopter.

"It's so slow..."

For the first time, Wang Zhilin felt that the server purchased from the institute was such a waste of time.

But no matter what, the problem at hand had to be solved by pointing to it, so Wang Zhilin had no choice but to punch the table in frustration.

It was another long wait, and it was not until the sun set that the second round of calculations was completed again.

Immediately afterwards, he stood up and took from the side a copy of the new standard GJB/Z89 issued not long ago by the Commission of Science, Technology and Industry for National Defense, and began to perform strength verification calculations.

But this time, when the verification results came out, Wang Zhilin saw the problem almost at a glance.

"The original design working load of the main reducer tail output bevel gear pair is 220kW, and the maximum power of the tail output is 285kW?"

This exaggerated number made him first think that he had just calculated it wrong.

Even if you don’t leave any margin, it actually exceeds the standard by nearly one-third?

This is the original structural design provided by the French!

No way?

It can't be that outrageous, right?

However, after checking the structural mechanics simulation results and strength verification results again, Wang Zhilin was very sure that there was no problem with his calculations.

In other words, there is something really wrong with the French design!